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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Iterating through an Array

idriss Elouilani
PLUS
idriss Elouilani
Courses Plus Student 1,232 Points
Posted by idriss Elouilani
idriss Elouilani
Courses Plus Student 1,232 Points

USE THE FOR LOOP

Use for or while loop to iterate through the values in the temperatures array from the first item --100-- the last --10-- inside the loop.log the current array value to the console.

script.js 
var temperatures = [100,90,99,80,70,65,30,10];
for (var i = 100; i<=100; i-=10){
  console.log (temperatures[100]);
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

2 Answers

Damien Watson
Damien Watson
27,419 Points
Damien Watson
Damien Watson
27,419 Points

Hi Idriss,

What the question is meaning is to loop from the first item in the array (item 0 => 100) to the last item in the array (item 7 => 10). Not to go from 100 to 10.

Starting with 'i' at the 0 position and incrementing until it hits the last position (temperatures.length). The output will also need to reflect the position (i) not (100)...

var temperatures = [100,90,99,80,70,65,30,10];
for (var i=0; i<=temperatures.length; i++){
  console.log (temperatures[i]);
}

Your previous code would have output an error because you are starting i at 100 and continuing forever while i is less than or equal to 100, and then subtracting by 10. It would continue past 0 and on into the negatives.

The error occurs because you are trying to get position 100 from the array which only contains 8 items, otherwise you'd be caught in an endless loop.

var temperatures = [100,90,99,80,70,65,30,10];
for (var i = 100; i<=100; i-=10){
  console.log (temperatures[100]);
}

Hope this helps.